00:00Mission status critical. The spaceship has hit a wall of fire somewhere past Pluto,
00:06where you'd expect to see nothing but total silence and icy darkness.
00:10The temperatures here reach 30,000 to 50,000 K, that's hotter than most stars.
00:16Yet there is no oxygen or actual flames. Is this the edge of our cosmic home brewing heat?
00:23Let's dive right in to find out.
00:25The Voyager probes launched in 1977 to explore all the planets.
00:30But their journey didn't end there.
00:32They kept going and became the first human-made objects to leave the solar system.
00:38Voyager 1 passed the heliopause in August 2012, and Voyager 2 followed in November 2018.
00:45The heliopause is like a cosmic finish line.
00:49It's where the sun-solar wind, charged particles streaming out,
00:52finally loses its fight against all the interstellar stuff.
00:57When Voyager crossed that line, instead of cold emptiness, scientists found scorching hot plasma.
01:03Like I said, there's no flame, just super-fast particles crashing into each other in ultra-thin plasma.
01:10They generate crazy temperatures with almost no heat transfer.
01:15Voyager 1's plasma detector failed back in the 1980s.
01:18But two other instruments recorded a sharp drop in solar particles and a surge in cosmic rays.
01:25Plus, there was a big distortion in the magnetic field.
01:28By the way, scientists expected the magnetic field direction outside the heliosphere to flip.
01:34But there was another surprise waiting for them.
01:37Voyager saw it aligned perfectly with the sun's magnetic field inside.
01:41Same alignment, just outside.
01:44Voyager 2 confirmed this wasn't a fluke.
01:47So, what's causing this alignment?
01:50Scientists think it's about how the interstellar field drapes around the heliopause, like wrapping cloth.
01:56It matches the sun's halo as they meet.
01:59Models show that in certain areas, magnetic reconnection, where magnetic lines break and reconnect,
02:05helps twist the interstellar field to line up with the solar one.
02:10Voyager 2 revealed that the outer region is actually denser and colder than the heliosphere.
02:15And the particles from inside are slipping through into space, like leaks in a cosmic ship's hull.
02:22As for Voyager 1, it even helped solve a cosmic ray mystery.
02:27Models thought particle counts would peak at the heliopause.
02:31But Voyager saw something the scientists called the Voyager Paradox.
02:35It turns out that our solar system doesn't have a clean, empty edge.
02:40It has a shockingly hot, magnetic, and complex boundary, where the sun's influence meets the galaxy.
02:48Voyager has proven that space isn't just static and cold.
02:52It's dynamic, turbulent, and unpredictable.
02:55We've cracked open the curtain and peeked at the weirdest frontier humans have seen.
02:59And we're still not even halfway through the story.
03:04Voyager 1 started acting strange back in November 2023.
03:08Its flight data system, which is like the spacecraft's brain, started sending a repeating pattern of gibberish.
03:15Normally, this system bundles up all the science data and engineering stats,
03:19like temperatures, voltages, and the spacecraft's heartbeat, and sent it to Earth in ones and zeros.
03:26But suddenly, the messages made no sense.
03:28Voyager 1's radio signal still reached Earth.
03:32But it was a steady, I'm-alive ping, without any useful info.
03:36After months of trial and error, they discovered the culprit.
03:40A single, stubborn memory chip that had gone rogue and corrupted about 3% of the system's memory.
03:47Nobody knows why it failed.
03:49Maybe it was just worn out after four decades.
03:52Or a high-energy particle from deep space hit it like a cosmic bullet.
03:56Since they couldn't replace the chip, NASA engineers had to pull off some scientific magic to fix this 46-year-old gadget.
04:05They divided the missing code into pieces and carefully moved them to other memory spots on the spacecraft.
04:12A radio signal takes 22 and a half hours to reach Voyager 1 and another 22 and a half hours to come back.
04:19So, NASA engineers were sending messages into the void and waiting almost two full days to see if it worked.
04:26On April 20th, Voyager finally responded with readable, coherent data.
04:31It was like getting a text back from a friend who's been ghosting you for months.
04:36Except this friend is 15 billion miles away, floating at the edge of the solar system.
04:41Voyager 1, as well as its twin, Voyager 2, was originally meant to last only 5 years.
04:49Both have gone through many challenges over their long journey.
04:52For example, a 7-month blackout in 2020 for Voyager 2.
04:57And a 2023 antenna mishap that required a shout command to get it pointed in the right direction.
05:03But, despite all that, they're still working hard and sending back extremely important data.
05:10Voyager 2 zoomed past Uranus back in 1986 and sent us pictures and data from billions of miles away.
05:18After looking at that data, scientists thought Uranus wasn't giving off much heat, which is weird for a giant planet.
05:25But now, thanks to years of spacecraft observations and fancy computer models,
05:31researchers have found Uranus does have its own internal heat.
05:35It's just subtle, only about 12.5% more than the sunlight it gets.
05:40That means the planet is slowly shedding leftover heat from its birth.
05:45Like a giant cosmic radiator cooling down after a superhot childhood.
05:50Its long 20-year seasons and tilted spin make the heat fluctuate.
05:54Figuring this out helps scientists understand how planets form, how atmospheres behave,
06:01and even give hints about Earth's climate.
06:04Voyager 2 might have just shown us a frozen, quiet world.
06:08But decades later, that data helped uncover a secret heartbeat under Uranus's icy blue clouds.
06:15As you can see, space loves plot twists.
06:19Let's hop to Saturn's tiny moon in Settilus.
06:22Scientists believe there's a massive ocean hidden under its frozen shell, and this moon's core is keeping it warm.
06:30And Settilus is small, about the width of Arizona.
06:33But it's one of the most promising places to look for extraterrestrial life.
06:38And that's because NASA's Cassini spacecraft caught it, spitting.
06:42Giant geysers of water were shooting out from cracks in its icy surface.
06:47Not only plain water, though.
06:49These plumes contain salts and organic molecules, including carbon, hydrogen, nitrogen, sulfur, and oxygen.
06:57These are the building blocks of life.
06:59And then, they also found phosphorus there.
07:02It's the rarest of the six elements upon which life depends.
07:06Together with sugars, it forms a skeleton for DNA molecules.
07:10The amazing part is that the concentrations of phosphorus on Settilus are at least 500 times higher than the highest known concentrations in our oceans.
07:21Scientists also studied the ice from Settilus.
07:24Plumes of water vapor freeze into snow on the surface here.
07:28And they found it might not be all shapeless dust like they thought.
07:32Up to a quarter of this ice can form tiny crystals, hiding like chocolate chips and cookie dough.
07:38They ran simulations, froze virtual water at crazy speeds, scrambled molecules, and even tested real ice with x-rays.
07:47Some ice is so odd that it has the same density as liquid water, so it neither sinks nor floats.
07:54It's all critical to know, as space ice could shield spacecraft, serve as fuel, or even show how building blocks of life travel to Earth.
08:03Scientists haven't found life or something life might have created on Settilus yet.
08:07But it looks like, if we find life anywhere in our solar system, this moon will be the first in line.
08:14Or maybe we'll hear some exciting news from the voyagers before it happens.
08:19They are still out there right now, flying through interstellar space.
08:24And some people are worried they could get damaged when they finally pass through the Oort cloud.
08:29Scientists haven't seen it directly, but many comets that visit us come from that region of space, stretching far beyond the Kuiper belt.
08:38The astronomer who supposed the cloud was real said it could contain around 100 billion comet-sized objects.
08:45Their total mass could be as heavy as Earth's.
08:48Sounds dangerous to the voyagers, but no worries.
08:51Scientists say the odds of them getting damaged are 100,000 times lower than your chances of winning a lottery jackpot.
08:59Oh well.
09:00So, the voyagers will keep sending faint signals for a few more years before their power runs out.
09:06After that, they'll just keep traveling.
09:08That's it for today.
09:12So, hey, if you pacified your curiosity, then give the video a like and share it with your friends.
09:17Or, if you want more, just click on these videos and stay on the bright side.
